Standard Exemption List

The facility shall not emit any chemical having a health
threshold limit value of less than 1 ppm as specified by OSHA or
ACGIH. This exemption does not apply to pilot plants using
chemicals for which an OSHA or ACGIH threshold limit does not
exist.

The facility shall emit less than one (1) pound per hour of any
air contaminant.

The plant is located at least 1/4 mile form any recreational
area or residence or other structure not occupied or used solely by
the owner of the facility or the owner of the property upon which
the facility is located.

The facility is constructed and operated only for the purpose
of:

(a) Testing the manufacturing or marketing potential of a proposed
product, or
(b) Defining the design of a larger plant, or
(c) Studying the behavior of an existing plant through modeling in
the pilot plant.

91. Any wet sand and gravel plant that
obtains its material from subterranean and subaqueous beds where
the deposits of sand and gravel are consolidated granular materials
resulting from natural disintegration of rock and stone and whose
plant production rate is 500 tons/hr or less. All permanent
in-plant roads shall be paved and cleaned as necessary or watered
as necessary to control the emission of dust to minimum level
possible under existing conditions.

94. Hydrochloric (muriatic) acid
storage tanks used exclusively for the storage of a 20% solution of
hydrochloric acid or less. If more concentrated acid is stored, the
tank vent must be scrubbed by a limestone, caustic or water
scrubber.

The plant is located at least 1/4 mile from any recreational
area or residence or other structure not occupied or used solely by
the owner of the facility or the owner of the property upon which
the facility is located.

During replacement of the iron oxide impregnated chips, the
unit is isolated from the main system and pressure is reduced to
0.5 psig or less through a gas fired flare.

The spent iron oxide chips being replaced are promptly disposed
of to avoid spontaneous ignition and avoid an odor nuisance.

96. Any elevated, vertical smokeless
flare system designed to be used only as an emergency relief system
provided that:

The flare is equipped with a continuously burning pilot light
plus either an automatic reignition system or an automatic alarm or
other system that provides immediate notification of appropriate
supervisory personnel that the flare pilot has gone out; and

The flare burns vent gases containing only carbon, hydrogen,
nitrogen, oxygen, sulfur, chlorine or compounds derived from these
elements; and

The flare height is at least 25 feet and the maximum
instantaneous emission of sulfur idoxide will be no more than 200
pounds her hour and maximum instantaneous emission of chlorine
containing compounds (calculated as chlorine) is no more than 10
pounds per hour; or

The flare height is at least 50 feet and the maximum
instantaneous emission of sulfur dioxide will be no more than 800
pounds per hour and the maximum instantaneous emission of chlorine
containing compounds (calculated as chlorine) is no more than 38
pounds per hour; and

There is normally no flow of process waste to the flare. The
flare is used only during an emergency; and

The heat release of the flare shall be greater than or equal to
the following values for flares emitting sulfur dioxide and/or
chlorine containing compounds.

There shall be no visible emissions from the flare for more
than five (5) minutes in any two (2) hour period except as provided
by the General Rules.

The flare is equipped with a continuously burning pilot light
plus either an automatic reignition system or automatic alarm or
other system that provides immediate notification of appropriate
supervisory personnel that the flare pilot has gone out.